If you've ever been a fan of The Simpsons, here's your chance to see all 552 episodes of the show in the longest single-series marathon in TV history. They'll be shown back to back, in sequential order, over 12 days and nights on the FXX cable network beginning Thursday.

The Simpsons holds the record as the longest-running prime-time scripted entertainment series in American TV history. In 1987, cartoonist Matt Groening's yellow-skinned Simpsons family — father Homer, mother Marge and the kids, brainy Lisa, bratty Bart and baby Maggie — began on TV as interstitial segments on Fox's The Tracey Ullman Show. The Simpsons got their own Christmas special in 1989, and their own prime-time series a month later, to kick off 1990 in very sassy style.

But in the beginning, the writers had a hard time finding a groove to perfect that style, Groening told Fresh Air's Terry Gross in a 1989 interview.

"It's been a real struggle to keep a certain roughness and abruptness and jerkiness," Groening said. "Working on this show, our animators ... all bring their own attitude and aesthetic philosophy to the project, and it's been a real struggle to make sure that everybody gets in line and has the same vision, at least looking in the same direction."

The Simpsons sparked a renaissance in TV animation that led to South Park and Family Guy. One writer, Conan O'Brien, found fame as a talk show host. Celebrities providing guest voices on The Simpsons included most major movie stars — and Paul McCartney, George Harrison and Ringo Starr. Its Treehouse of Horror Halloween specials have become one of TV's most inventive annual traditions.

And along the way, year after year, The Simpsons has served up occasional flashes of comic genius, according to TV critic David Bianculli. There was the Season 4 episode that presents a Springfield community-theater musical production of A Streetcar Named Desire — and the Season 2 episode that has Marge Simpson, voiced by Julie Kavner, so upset about the violence in the Itchy & Scratchy cat-and-mouse TV cartoons her kids watch that she goes on TV herself, on a Nightline-type talk show, in protest.

So why would people be interested in the marathon?

"There's something about the sense of watching at the same time as other people that makes it special," says Bianculli. "That certainly goes for a marathon — and that's why I predict this 25-season Simpsons marathon will indeed steer people towards FXX. It's a great show, a great idea and a TV viewing event of unprecedented scale."

Since The Simpsons began, Gross has interviewed many people who have had a hand in creating the show — from Matt Groening in 1989 and 2003 totwo of the writers, Al Jean and Mike Reiss, in 1992. Gross also talked with actors who do the voices, including Nancy Cartwright, who plays Bart, in 2007; Julie Kavner, the voice of Marge, in 1994; and Hank Azaria, the voice of Moe, Apu, Chief Wiggum and others, in 2004.

We listen back to these interviews in Fresh Air's appreciation of The Simpsons.

Interview Highlights

Creator and cartoonist Matt Groening, interviewed in 2003

On how the vision has changed over the years and on taking risks

The problem with doing a sitcom, which has lasted more than 300 episodes, is you're trying not to repeat yourself, you're trying to surprise the audience, and you're trying to keep everybody who works on the show surprised. As a result, the show has gone off in some very peculiar directions. Sometimes, I was alarmed, "We can't do this!" And then it turns out to be OK.

One of the great things we did last year is we parodied the Fox News Channel and we did the crawl along the bottom of the screen. And Fox fought against it and said that they would sue the show, and we called their bluff because we didn't think Rupert Murdoch would pay for Fox to sue itself. So we got away with it, but now Fox has a new rule that we can't do those little fake news crawls at the bottom of the screen, in a cartoon, because it "might confuse the viewers into thinking that it's real news."

On getting into trouble with the Fox network

At the beginning, virtually anything we did would get somebody upset, and now it seems like the people who are eager to be offended — and this country is full of people who are eager to be offended — they've given up on our show. We got into trouble a few years ago for — Homer is watching an anti-drinking commercial and it said, "Warning! Beer causes rectal cancer." And Homer responds by saying, "Mmm, beer." Fox didn't want us to do that because beer advertisers are a big part of the Fox empire, and it turns out the writer was able to track down the actual fact where some studies show that indeed it does — or did or has a tendency to [cause cancer] — so we were able to keep it in.

On Homer's religious neighbor, Ned Flanders

Originally Ned Flanders was just the wacky neighbor who was supposed to be just a complete annoyance to Homer for no good reason. And then we realized that he was an object of mirth with his strong religious feelings. We thought, "How do we create a religious character who is not the usual stereotype?" And we made him a truly good guy, and his beliefs are sometimes a little annoying but he's not a hypocrite, he's real. We get lots of fan mail for him, and we get lots of photos of people who look exactly like Ned Flanders.

Showrunners Al Jean and Mike Reiss, interviewed in 1992

On the production process

Al Jean: The first thing we do is write the script and then record the audio track with the cast.

Mike Reiss: We record it like a radio show. It takes about eight hours and we cut it down to about 19 minutes of audio track, and then that's sent to the animators, who expand it to about 24 minutes.

Jean: We have a team of about six guys who are terrific. They direct the way a movie director directs a feature. They take the script and they pretty much stage the whole thing, design the characters, and then we see a real rough version in black and white called an "animatic." We do some rewrites there, and then we send the whole thing to Korea — and that's where the actual color animation is done, and it comes back about three months later.

Reiss: It's sort of a good thing, which is we throw in some topical allusions, but I think [the show] will be a little timeless because we can't ride every current thing and get a quick laugh about something that's in the news right now.

Actors

Nancy Cartwright (Bart Simpson and others), interviewed in 2007

On doing multiple voices in one conversation

There was one show ... there was a scene where it was Bart, Nelson, Ralph and Kearney, I believe, and the scene was like three pages long and I was just talking to myself the entire time. I remember doing it at the table read. I was so nervous to do it — [there were] like 100 people in the room, [and I was] just praying that I wouldn't get confused who I was. And I finished my run and I was sweating and ... out of breath, there's no time to even breathe, practically, that is such a challenge.

On children learning she is the voice behind Bart

Parents will come up to me — and I know they really want to hear me do the voice — but there's a 3-year-old clutching onto Mama's skirt, and they're saying, "Could you do it for Sally?" And I'm thinking ... [the kid] looks scared to death. If I was to lean down and said, "Hi! I'm Bart Simpson, who the hell are you?" — you think that kid is going to like it? Kids look at me like I'm an alien or they get upset. I just say, "I'll do it for you, but I'm not going to do it for your child." I just think that that's wrong. ...

It's too big of a concept. ... They might watch The Simpsons, but a child, I really don't think [the parents] are watching through a child's eyes. [Kids] enjoy the colors and they like the different expressions and emotions that they see, whereas a teenager will pull something totally different out of that. They will start to recognize references — and, of course, adults, we can get the satire. ... There's a whole cross-generational span of The Simpsons that entertains those audiences. But a kid? I don't know, man. I don't know how old I was before I realized that those sounds came from actors. ... I use some discretion on who I just throw that voice to.

Julie Kavner (Marge Simpson), interviewed in 1994

On having a naturally husky voice

I was born this way. I came out of my mom and said, "Hello Rose. Hello Dave." They used to send me home. They always used to think I had laryngitis. ... [I'm from Los Angeles and] my parents are from New York, and they taught me how to speak English so that's why I sound like this, as opposed to something lovely.

Hank Azaria (Moe, Apu, Chief Wiggum and others), interviewed in 2004

On singing in character

It's much easier for me to sing in character; it's much more difficult for me to sing in my own voice. It's much easier for me to sing as Wiggum or Apu or even as Moe. I think I'm just more comfortable with the mask, the vocal mask. ... I'm not embarrassed to do that, but I'd be embarrassed to do the same thing in my own singing voice — it's weird.

Copyright 2014 NPR. To see more, visit http://www.npr.org/.

Transcript

TERRY GROSS, HOST:

This is FRESH AIR. I'm Terry Gross. The longest single series marathon in TV history starts tomorrow. All 552 episodes of "The Simpsons" will be shown back to back, in sequential order, over 12 days and nights on the FXX cable network - the lesser-known sibling of the FX cable network. It's a move clearly designed to get attention, and at least for us, it's done just that. We're devoting our whole show today to "The Simpsons." We'll hear interviews from our archive with the creator of the series, two of the writers and several actors who do the voices, including Nancy Cartwright, who plays Bart. Let's start with an appreciation from our TV critic David Bianculli.

DAVID BIANCULLI, BYLINE: There are two main things to consider here - first, there's the popularity and durability of "The Simpsons." The animated Fox series begins its 26th season this fall. And now holds the record as the longest-running scripted entertainment series in TV history. Then, there's the popularity of the TV marathon, which, despite the availability of most TV series on DVD or streaming services, is a programming stunt that continues to work. Cartoonist Matt Groening's yellow-skinned Simpsons family - father Homer, mother Marge - and the kids - brainy Lisa, bratty Bart, baby Maggie - began on TV as interstitial segments on Fox's "The Tracey Ullman Show" in 1987. They got their own Christmas special in 1989 and their own prime-time series a month later, to kickoff 1990 in very sassy style. In other words, "The Simpsons" has been around a long time. So have I. Here's how I previewed that series on FRESH AIR almost 25 years ago.

(SOUNDBITE OF ARCHIVED BROADCAST)

BIANCULLI: When it premieres as a regular series this weekend, "The Simpsons" will become the first prime-time cartoon series since the '60s - the days of "The Jetsons" and "Jonny Quest" and "The Flinstones. If "The Simpsons" is close in spirit to any of the shows from that era though, it's to Rocky and Bullwinkle, which I loved as a kid. Who am I kidding? I love it now. And I love "The Simpsons" too. It's just as funny, just as outlandish and just as subversive.

Since then, "The Simpsons" has just about done it all. It sparked a renaissance in TV animation that lead to "South Park" and "Family Guy." One writer, Conan O'Brien, found fame as a talk-show host. Celebrities providing guest voices on "The Simpsons" included most major movie stars, an uncredited Michael Jackson and on separate occasions, Paul McCartney, George Harrison and Ringo Starr. Its Treehouse of Horror Halloween specials have become one of TVs most inventive annual traditions. And along the way, year after year, "The Simpsons" has served up occasional flashes of comic genius. There was the season four episode that presents a Springfield community theater musical production of "A Streetcar Named Desire." And the season two episode that has Marge Simpson, voiced by Julie Kavner, so upset about the violence in the Itchy and Scratchy cat and mouse TV cartoons her kids watch, that she goes on TV herself, on a "Nightline" type talk show, in protest. Harry Shearer plays that show's host and Marge quickly finds herself up against Itchy and Scratchy's producer, voiced by guest star Alex Rocco.

HARRY SHEARER: (As Kent Brockman) Hello, I'm Kent Brockman. And welcome to another edition of Smartline. Are cartoons too violent for children? Most people would say no, of course not. What kind of stupid question is that? But one woman says, yes. And she's here with us tonight. Mrs. Marge Simpson. Also with us for this animated discussion (laughing) Roger Meyers, chairman of the board of Itchy and Scratchy International.

ROCCO: (As Roger Meyers) Give me a break. I think that is a bunch of baloney. And here's why - in preparing for this debate, I did a little research and I discovered a startling thing. There was violence in the past long before cartoons were invented.

SHEARER: (As Kent Brockman) I see, fascinating.

ROCCO: (As Roger Meyers) Yeah, and there was something called The Crusade, for instance - tremendous violence, many people killed. The darn thing went on for 30 years.

SHEARER: (As Kent Brockman) And this was before cartoons were invented?

BIANCULLI: There are those who say that the first years of "The Simpsons" are by far the best and the funniest. But if you've kept watching, you've seen such recent bits of brilliance as the Simpsons' trip to Israel in 2010 and this year's ambitious Lego episode, "Brick Like Me." And you can see them all if you want, starting at 10 a.m. Eastern time on Thursday and continuing through September 1. But why should you watch? Most previous episodes of "The Simpsons" are available on DVD. And reruns air all the time in syndication on local television. What makes a marathon, even a mega-marathon like this one, such a big deal? I'm glad I asked. The popularity of TV marathons, whether they're annual two-day bursts of "Twilight Zone" episodes on sci-fi or complete run repeats of "Breaking Bad" or the "Walking Dead" on AMC, give viewers a chance to dive in at any time and feel a sense of community. That's something that's lacking when Netflix puts up an entire season of an original series for instant viewing. Having a TV series up in some Internet cloud somewhere is like having a DVD set somewhere in my basement - just because I can get to it doesn't mean I will. Yet on TV, whenever a marathon of an old show I love is on television, I'll invariably be sucked in, just as I am whenever some network shows "Jaws" for the zillionth time or "Butch Cassidy And The Sundance Kid" or "All The President's Men." It doesn't matter that I already own those movies, often in more pristine copies that are never interrupted or edited. There's something about the sense of watching at the same time as other people that makes it special. That certainly goes for a marathon. And that's why I predict this 25 season "Simpsons" marathon will indeed steer people towards FXX. It's a great show, a great idea and a TV viewing event of unprecedented scale. And just think - in less than two weeks of uninterrupted viewing, you can see every variation on "The Simpsons" opening credits couch gag.

(SOUNDBITE OF "THE SIMPSONS" OPENING CREDITS)

GROSS: David Bianculli is founder and editor of the website TV Worth Watching and teaches TV and film history at Rowan University in New Jersey.

We're going to hear next from three actors who do voices on "The Simpsons," starting with Julie Kavner, the voice of Marge Simpson, who is Homer's wife and the mother of Bart, Lisa, and Maggie. In the 70s, Julie Kavner co-starred on the sitcom "Rhoda" as Rhoda Morgenstern's sister Brenda. I spoke with Kavner in 1994.

(SOUNDBITE OF ARCHIVED BROADCAST)

GROSS: So how do you change your voice to become Marge?

KAVNER: I roughen it up and I raise it a bit. I raise it an octave or so.

GROSS: Can you do a little?

KAVNER: (Imitating Marge Simpson) It's just kind of up there like that and a little more tired.

GROSS: Right. Now does it hurt your voice to do that?

KAVNER: Not at all. The sisters, on the other hand, the two twin sisters, are an octave lower. Do I have a range, or what, Terry?

GROSS: (Laughter) That's great. You have a wonderful voice. Was your voice husky when you were young?

KAVNER: Yeah, I was born this way. I came out of my mom and said, hello, Rose. Hello, Dave.

(LAUGHTER)

GROSS: But, did you have a deep voice when you were young?

KAVNER: Yeah, they used to send me home. They always used to think I had laryngitis.

GROSS: Who, the nurses? You have a very New York voice but you grew up in Los Angeles. So...

KAVNER: Well, Rose and Dave who I just mentioned to you? My parents, they're from New York and they taught me how to speak English, you see? So that's why I sound like this, (imitating English accent) as opposed to something lovely.

(LAUGHTER)

GROSS: Julie Kavner recorded in 1994.

Hank Azaria voices several characters on "The Simpsons" including Moe the bartender, police chief Wiggum and Apu, the owner of the Kwik-E-Mart. I spoke with Hank Azaria in 2004.

(SOUNDBITE OF ARCHIVED BROADCAST)

GROSS: How did you get to be on the Simpsons? And two of the voices you do are Moe, the bartender, and Apu who runs the convenience store, the Kwik-E-Mart.

HANK AZARIA: (Imitating Moe) Yes, that's correct. I'm - Moe was the first voice I did. There's a little Moe for you there. (Imitating Apu) And Apu is actually the third voice I believe that I did. And I was 22-years-old. This was a long time ago. I'm 40 now. I was 22-years-old and hadn't worked much. There was an original voice of Moe the bartender that I guess they weren't too happy with and wanted to replace. And I did this voice, and I was doing a play at the time in LA or I was playing a drug dealer. And I was sort of doing a bad Al Pacino impression in the play from"Dog Day Afternoon." (Imitating Al Pacino) I was sort of talking like this, like Al kind of sounded in "Dog Day Afternoon." And I said what about that voice? They were like, well, we want Moe to be gravelly. So, I just made that voice gravelly and it sounded like that. The next week I did Wiggum. (Imitating Chief Wiggum) Chief Wiggum, chief of police talks like this. Then I did Apu. And then after - about midway through the second season they made me a - they gave me a contract. They made me a regular. By that point I was doing like five or 10 voices.

GROSS: Do you have a favorite Moe scene?

AZARIA: Favorite Moe scene - there's been - he's one of my favorite characters. You know, one of my favorite times is when Moe is asking a girl out. And he says to her (Imitating Moe) that he's going to go out and buy her a steak the size of a toilet seat.

GROSS: (Laughing).

AZARIA: That one sort of stayed with me.

GROSS: (Laughing) You've had to sing as Apu.

AZARIA: (Imitating Apu) I have had to sing as Apu. It's true.

GROSS: Is it hard to sing in character?

AZARIA: It's much easier for me to sing in character. It's much more difficult for me to sing in my own voice. It's much easier for me to sing as Wiggum or as Apu or even as Moe.

GROSS: Why is that?

AZARIA: I think I'm just more comfortable with, you know, the mask, you know, the vocal mask. (Imitating Wiggum) You know Chief Wiggum like this - it's hard - easier to sing like this than it is to sing - I'm just - I'm not embarrassed to do that, but I'd be embarrassed to do the same thing in my own singing voice. It's weird.

GROSS: Hank Azaria, recorded in 2004.

The voice of Bart Simpson is performed by Nancy Cartwright. She's aged over 25 years since she started doing Bart, but Bart remains a child and Cartwright remains convincing. When I spoke with Cartwright in 2007 she told me about auditioning for "The Simpsons."

(SOUNDBITE OF ARCHIVED RECORDING)

NANCY CARTWRIGHT: So I went in and shook Matt Groening's hand, and I said, you know, I'm here to read for Lisa, but I saw the part for Bart and I'd rather read for him. Do you mind? And he said, no that's fine. So I gave him one shot, one take, one sound, one voice -and that was it. (Imitating Bart) Blah, blah, blah, blah, blah, blah, blah, blah, blah.

And Matt, his eyebrows went up, his tongue came out of his mouth. He's like oh, my God - that's him. That's Bart. That's him. You got the part. And I was given the part on the spot.

GROSS: So there's nothing conscious going on when you do the voice - it just came to you?

CARTWRIGHT: Yeah. It just - no kidding - when I saw the picture - it really helps when you get the visual image of what the character looks like. Because sometimes, you might have a character whose jaw is sticking out a little bit more on the bottom than it is on the top and he's got this sort of - (imitating animated voice) there's a placement there so you know that his lower teeth would be sticking out a little bit farther - so that would help in creating a character. Or, say you've got a 7-year-old kid who's got a split in his two front teeth, or he's missing one of his teeth at age 7 - (imitating animated voice) so he would be talking sort of like this and can put sort of a sound in there, sort of like that little actress that played on "Mrs. Doubtfire."

So I can steal from, you know - Mara Wilson, I think, was that little actress's name - and I totally ripped that off from her. When I go to the mall or just, you know, people-watching, or I go to movies and watch television, I'm inspired by live-action actors and recognizing sounds and trying to duplicate that. So I come up with an arsenal of characters in my head, so then I can then at the next audition give them more options.

GROSS: Well, why don't you describe who Nelson is and how you came up with his voice?

CARTWRIGHT: Well, Nelson - he was a bad boy and I had to read the script because there's not much of a description in the script. It might say, bad boy, but it didn't go into detail on it. So by reading the script and you know, putting that in context, I realized he was just this - he was a thug. He was bigger, physically, than Bart so - he was also, I believe, Nelson Muntz is a little bit older, even though he's in the fourth grade. But I just ended up coming up with a sound that - I think Nelson has sort of evolved and came to the point where he (imitating Nelson Muntz) eventually got a really, really rough sound like that. And he has got a (imitating Nelson Muntz) really hard Rs.

And I don't know, that's how that sound came. And the laugh; ha ha - let me just say it (imitating Nelson Muntz) ha ha. That was written in the script as, it just said, I think it actually just said, ha ha. And I don't know, if somebody else would've been cast as that they would've come up with their own idea of what that would sound like. But when I did that, it got an instant laugh. And so that stuck. And because I think, it got that laugh, the writers put a little asterisk or little star beside that and they know that later on, they can do that again and hopefully it'll continue to get a laugh. And it's through trial and error and through experimenting. I don't think anybody said, let's create a signature laugh for Nelson Muntz. Do you know what I mean? It's just something that sort of evolved. And I find that fascinating too and looking at the development of "The Simpsons," that a lot of choices that we had the opportunity to make, they were just opportunities that we had. Nobody was going out there and saying, wow, when I do this, this is going to become a catchphrase. Next thing you know, this is (imitating Nelson Muntz) smell you later - that people are going to be saying that. You know?

(LAUGHTER)

GROSS: When you do that gruff, like, Nelson voice, does that hurt your vocal chords at all? Like, is there a way of doing that without it hurting?

CARTWRIGHT: You know, he truly is my - he's the most challenging, in terms of my vocal chords, but, throughout the years and the 400-plus episodes that we've done so far, Nelson has only really been a lead character or citizen you know, in just maybe a couple or three. One of my favorite ones was when there was that tribute when he came home and Marge really kind of took him under his wing and he sang that song, it was a tribute to - it was like a play on Yentl. (Laughter) I don't know if I can do it. (Singing, imitating Nelson Muntz) Papa, can you hear me?

(LAUGHTER)

CARTWRIGHT: Singing to his father because his father like, left to go get cigarettes or milk or something, at the Kwik-E-Mart and he never came - (imitating Nelson Muntz) Papa, is that you? Is that you? Oh, papa.

GROSS: That was Nancy Cartwright, the voice of Bart Simpson, recorded in 2007. We'll hear more from that interview after a break as we continue our tribute to "The Simpsons." This is FRESH AIR.

(MUSIC)

GROSS: This is FRESH AIR. Let's get back to our interview with Nancy Cartwright, who does the voice of Bart Simpson, as well as the voice of Bart's friend, Nelson. We spoke in 2007, when "The Simpsons" movie was released.

(SOUNDBITE OF ARCHIVED BROADCAST)

GROSS: In the new "Simpsons" movie, as in the TV show, there are times when Homer strangles Bart.

CARTWRIGHT: Oh, sure.

GROSS: So can you talk about what goes on between you and Dan Castellaneta when Homer's strangling Bart?

CARTWRIGHT: You know, that's another great one. I remember the first time that it was written in the script that that happened and I was just kidding. I said, Dan, why don't you come over and help me out. He did. He came across this - you know, he was standing on the opposite side of me - walked all across the studio, stands behind me, he started choking me. And I'm going (making choking noises) and it like, created that. And man, it was imprinted forever and that's what we duplicated from then on out.

GROSS: Am I right in saying - from based on your description - that when you're recording like, "The Simpsons" movie or the TV show, that all the actors are in a room together gathered around one or two microphones, but you're doing it in real time as a group?

CARTWRIGHT: Yeah, that's absolutely correct.

GROSS: OK.

CARTWRIGHT: Yeah. It's ideal. It's ideal that we're there so that we can kind of play off of each other.

GROSS: What's it like when you're doing both sides of the conversation? Say like, Bart's talking to Nelson.

CARTWRIGHT: (Laughter) Yeah, that's fun. That's really, really fun. There was one show, I think it was a take on the - I think it was called "Bart's Commandments" or - it was some Ten Commandments show; it was a play on - took you back in time. And there was a scene where it was Bart, Nelson, Ralph and Kearney, I believe. And oh, my God, the scene was like, three pages long and I just talking to myself the entire time. I remember doing it at the table read. I was so nervous to do it in front of that - there's like a hundred people in the room - and I'm doing it, just praying that I wouldn't get confused who I was. And I finished my run. I mean, I was sweating (laughter) I was like, really perspiring and I was out of breath. There's no time to even breathe, practically. That is such a challenge. And yet, I mean, but if it's just like, one scene - there was one scene where Bart had a Mr. Microphone and he was in the bottom well pretending like he was somebody else, and Rod and Todd Flanders were next-door and they were picking him up on their radio. And Bart's like, (imitating Bart Simpson) Rod, Todd - this is God.

He goes, (imitating Todd Flanders) what are you doing on our radio?

(Imitating Bart Simpson) What do you mean, what am I doing on the radio? I created the universe, stupid kid.

(Imitating Todd Flanders) What do you want from us?

(Imitating Bart Simpson) I want you to go to the kitchen and bring forth all the cookies from your kitchen.

(Imitating Todd Flanders) But, those are our parents' cookies.

(Imitating Bart Simpson) What do you want - a happy God, or a vengeful God?

(Imitating Todd Flanders) Happy God, happy God.

(Imitating Bart Simpson) Then bring forth the cookies.

(Imitating Todd Flanders) Yes, sir.

(LAUGHTER)

CARTWRIGHT: It's a challenge, but it's fun.

GROSS: That's so great.

GROSS: Nancy Cartwright, the voice of Bart Simpson, recorded in 2007. We'll hear more from Cartwright and hear from the creator of "The Simpsons" in the second half of the show. The 12-day "Simpsons" marathon begins tomorrow morning on the FXX cable network. I'm Terry Gross and this is FRESH AIR.

AZARIA: (Imitating Apu Nahasapeemapetilon) Hello gents, what will it be?

GROSS: This is FRESH AIR. I'm Terry Gross. Tomorrow, the longest single series marathon in TV history begins on the FXX cable network, featuring all 552 episodes of "The Simpsons" in sequential order. That's inspired us to go into our archive and bring out some of our interviews with people behind the show. Let's get back to our 2007 interview with Nancy Cartwright who does the voice of Bart Simpson. The actors record the voices before the story is animated.

(SOUNDBITE OF ARCHIVED BROADCAST)

GROSS: Is there ever a time when you were given a script and you're thinking, I really need to see a visual to get what's going on here, to get what Bart is actually experiencing?

CARTWRIGHT: Wow. That's another great question. No. Actually, no. But I think, partially, is that after - especially after all these years, we can totally visualize what's going on. But you just got to do your homework. You've just got to be prepared and know that if Bart is, you know, on a skateboard or he's, like, riding his bicycle over a cliff and down a hill, that there's going to be (imitates gasping noises), you know? And I just visualize it and, like, how many seconds of this do you want? Well, make it a little bit longer. Do it again, but make it longer. And Nancy, you know what, this isn't a show about him riding, you know, his bicycle over a cliff. Just cut it. Like, you got to cut that about - just give me about a tenth of that. Yeah, OK, good, no problem 'cause I don't know about the length of time for the animation.

GROSS: You said earlier that, you know, when, like, a lot of friends of yours who have children or, you know, people you are just meeting have children will introduce the kids to you and say, this is Nancy Cartwright, and she does the voice of Bart. And then they'll expect you to do the voice of Bart for the kids. What about your own kids? I mean, they grew up while you were doing "The Simpsons." Did they do, like, Mommy, Mommy, do Bart for us?

CARTWRIGHT: As a parent, you kind of wonder what kind of influence you have on your kids in everything that you're doing, whether it's traveling, you know, to different countries or whatever. When my son, Jack, was two years old, they had come out with a Bart Simpson - it was a prototype to see if the talking Bart doll would work. But the string on the thing was a little short, so it sort of sounded like Bart on helium because it would be like, (imitating Bart Simpson) don't have a cow man. Don't have a cow man. But my son would pull the string and it would say that. And he'd look at the string, and then he'd look at me. Then he'd pull it again. (Imitating Bart Simpson) Don't have a cow man. And then he'd look at me, and he said to me, Mommy, I don't see you in there. I don't see you in there. (Laughter) He's two years old. I'm telling you, that concept -parents will come up to me and, you know, I know that they really - they want to hear me do the voice. But there's a three-year-old clutching onto momma's skirt. And they're saying, could you do it for Sally? Could you - and I'm thinking, I'll just tell the parent I don't have any - I don't have anything vested in this for a three-year-old kid that looks scared to death. If I was to lean down and say, (imitating Bart Simpson) hi, I'm Bart Simpson. Who the hell are you? You think that kid is going to like it? Kids look at me like I'm, you know, an alien. They get upset. So I'll just say, look, I'll do it for you, but I'm not going to do it for your child. I just think that that's wrong. It's too big of a concept.

GROSS: Why do the kids get so upset?

CARTWRIGHT: Well, it's just - it's too big of a concept. They're looking at this woman who - they might watch "The Simpsons," but a child - I really think that they are watching it through a child's eyes, and they enjoy the colors and they like the different expressions and emotions that they see. Whereas as a, you know, a teenager cull something totally different out of that. They will start to recognize references. And, of course, adults - I mean, we can get the satire. And we can get more, you know, of the history and even more references than a teenager would get. So there's a whole cross-generational span of "The Simpsons" that entertains those audiences. But a kid - I don't know, man. I don't know how old I was before I realized that those sounds came from actors. It's a concept that's pretty - you know, I'd say 5 and under just - this is a gross generalization. There are exceptions to the rule, no doubt about it . But generally speaking, I use some discretion on who I just throw that voice to.

GROSS: Well, Nancy Cartwright, it's just been so much fun to talk with you. Thank you so very much.

CARTWRIGHT: Yeah, you bet.

GROSS: Nancy Cartwright, the voice of Bart Simpson recorded in 2007. We'll hear from the creator of "The Simpsons" and from two of its original writers after a break. This is FRESH AIR.

(MUSIC)

GROSS: This is FRESH AIR. Today, we are paying tribute to "The Simpsons" in anticipation of the 12-day marathon featuring all the episodes in sequential order that begins tomorrow on the FXX cable network. One of classic episodes, which has been a favorite in the FRESH AIR office, is about Marge going on a crusade against cartoon violence. Here she is writing a letter to a TV executive played by Alex Rocco, who played Moe Greene in the "Godfather."

(SOUNDBITE OF TV SHOW, "THE SIMPSONS")

KAVNER: (As Marge Simpson) Dear purveyors of senseless violence, I know this may sound silly at first, but I believe that the cartoons you show to our children are influencing their behavior in a negative way. Please try to tone down the psychotic violence in your otherwise fine programming. Yours truly, Marge Simpson.

ROCCO: (As Roger Meyer) Take a letter, Miss White. Dear valued viewer, thank you for taking an interest in the Itchy and Scratchy program. Enclosed is a personally autographed photo of America's favorite cat and mouse team to add to your collection. In regards to your specific comments about the show, our research indicates that one person cannot make a difference no matter how big a screwball she is. So let me close by saying...

KAVNER: (As Marge Simpson) And the horse I rode in on? I'll show them what one screwball can do.

GROSS: I talked about that episode with Al Jean and Mike Reiss in 1992. They're two of the original writers on "The Simpsons" and became producers and showrunners. I asked why the writers had Marge campaign against cartoon violence.

(SOUNDBITE OF ARCHIVED BROADCAST)

AL JEAN: The cartoons that they watched on "The Simpsons" - "The Itchy and Scratchy Show" were extremely violent. So she led a crusade and actually got them to tone down their violence. The cartoons were really pathetic without violence. They were really lame. So kids didn't watch them and they went out and they started, you know, riding bikes and building things and having fun. And, you know, it seemed like a golden age but then Michelangelo's "David" was headed toward Springfield and then the same people who wanted to censor cartoons wanted to put pants on the statue. And Marge realized that you can't really censor one thing without saying that censorship is OK in all forms. For a children's show - or, you know, quote, unquote, "children's show" - it really had a lot to say.

MIKE REISS: And also it's sort of typical of "The Simpsons" episode, which is it made a lot of points that all canceled each other out. The show really doesn't have a platform.

JEAN: The other thing is we're sort of crusading against violent cartoons. But, of course, we got to show about 10 minutes of very violent cartoons (laughter). So we're playing both ends against the middle.

GROSS: Well, the violent cartoons that you show are itchy and scratchy, which kind of regularly appear in the series. And, I mean, all they do is just kind of, like, beat on each other with a hammer. There is no plot. There's not even as much plot as there is in a road runner cartoon. It's just hitting each other...

JEAN: No. In fact, they usually - they average about six seconds long.

(LAUGHTER)

JEAN: So if it was a real cartoon, you really wouldn't, you know, get much out of them.

REISS: We also - we generally even spend longer writing the title of the cartoon than writing the rest of it - something like "Bang The Cat Slowly..."

(LAUGHTER)

REISS: ...Was one title and that took about two hours. And the rest of the cartoon was pretty easy to do.

GROSS: Now, how do you work with the animators? Do you write the scripts first and then hand it over to them?

JEAN: Yeah, the first thing we do is write the script and then record the audio track with the cast.

REISS: We record it like a radio show. It takes about eight hours and we cut it down to about 19 minutes of audio track. And then that's sent to the animators who expand it to about 24 minutes.

JEAN: We have a team of six guys who are terrific. You know, they direct the way a movie director directs a feature. And, you know, they take the script and they pretty much stage the whole thing, design the characters. And then we see a real rough version in black and white called an animatic. We do some rewrites there. And then we send the whole thing to Korea. And that's where the actual color animation is done. It comes back about three months later.

GROSS: You are really working far ahead.

REISS: It's sort of a good thing, which is - we throw in some topical allusions, but I think it's going to make the show a little more - it'll be a little timeless because we can't ride every current thing and get a quick laugh off of something that's in the news right now.

JEAN: A bad thing that happens is we'll use a name like Rex Harrison or somebody and then he'll die before the show airs so we have to change it. It's sort of like there's a curse. And then we did a big joke about the Soviet Union and it died. So we have to just kind of be careful.

REISS: We did a little thing where Jackie Mason appeared on the show and they flew to New York to record him. And he just made some reference to Isaac Bashevis Singer. And then a couple of months later, we're reading the paper - Isaac Bashevis Singer dies. Isaac Bashevis Singer dies, oh no. And we had to fly back to New York and get him to replace the line with Saul Bellow. And then, for the next two months, we were praying Saul Bellow, please don't die. And, you know, these prayers were going out to him and I think he didn't know why.

GROSS: As professional comedy writers, do you quip a lot around the house like characters in sitcoms always do?

JEAN: At home, it's more like oh, I'm so tired (laughter). Like oh, there's the baby, I'd better go say hello. We do have a lot of laughs around the office, but it's never about the script.

REISS: Yeah.

JEAN: The fun stuff is always talking about, you know, the elections or, you know, things that when we're wasting time and we're not, you know, doing things that are connected with the show, that's fun.

REISS: It's really as funny as it gets. It'll be rolling and everyone's laughing and then someone's got to say well, let's get back to those damn Simpsons.

GROSS: Al Jean and Mike Reese recorded in 1992.

"The Simpsons" was created by Matt Groening, who had previously been best known for his syndicated comic strip "Life In Hell," starring a rabbit with bulging eyes and an overbite, similar to the facial features he gave to the Simpsons. He created "The Simpsons" as a series of animated shorts for Tracey Ullman's variety show. I spoke with Matt Groening in December 1989, just before "The Simpsons Christmas Special" that launched "The Simpsons" weekly primetime series. I asked him if he'd described "The Simpsons" as an animated sitcom.

(SOUNDBITE OF ARCHIVED BROADCAST)

MATT GROENING: They're more like a hallucination of a sitcom for me. Anyway, I'm so used to drawing my cartoons and not having them move that when I see these characters actually come to life and strangle each other and shout and yell and laugh and scream, it's like hallucinating, at least for me. And I hope that that experience will be the same for the rest of America.

GROSS: So now that you have all these talented artists drawing your characters, do you ever worry that something of the edge will be lost in the characters because there's a smoothness that they could bring to the drawings?

GROENING: Yeah, it's been a real struggle to keep the - to keep a certain...

GROSS: Roughness?

GROENING: Yeah, roughness and abruptness and jerkiness on -working on this show are animators from Hanna-Barbera and Disney and great, virtuoso, independent projects. And they all bring their own attitude and ascetic philosophy to the project. And it's been a real struggle to make sure that everybody gets in line and has the same vision and is at least looking in the same direction. As an example, almost every animator today worships Tex Avery.

GROSS: Tex Avery is one of the "Looney Tunes" guys?

GROENING: One of the "Looney Tunes" guys that did - you know, he's the guy that had eyeballs popping out of people's heads and their tongues falling to the floor and very exaggerated, very violent, really jazzy stuff - brilliant stuff. And that's not what we're trying to do in "The Simpsons." With our cartoon effects are not (imitating cartoon sounds) you know, all those kind of crazy effects that you got imprinted on your brain. They're more realistic. And it's a slightly different kind of humor. And it takes a while to get the hang of.

GROSS: Did you have to draw - I don't know if it's called the Bible or not - but did you have to draw what each of your characters look like from different angles and in motion so that the animators would know how the characters look?

GROENING: Yes, my stuff is basically - I see it two-dimensionally. It's very flat. And I draw my characters almost always from a three-quarter profile. And the animators had to come up with ways of showing them from straight on and from behind. Those are angles that I rarely, if ever, use in my own work. But even tougher than that was we created an eight-inch high Bart head in clay for the Bart Simpson talking doll, which is due in your local toy stores if the show is a hit. And I'm really proud of this doll because he gets to say a number of outrageous things. The only thing the toy company wouldn't let me have him say is, I'm Bart Simpson, who the hell are you? They thought that that was too much to come out of a kid's toy. They also wouldn't let him burp which I was very disappointed by. But maybe that in the next time.

GROSS: So what does he say?

GROENING: My favorite thing is kids in TV Land, you're being duped. I had a lot of flak over that because they said kids aren't going to know what the word duped means. So I offered the substitute brainwashed but they didn't go for that.

GROSS: Matt Groening, the creator of "The Simpsons," recorded in 1989 just before the launch of the show. I spoke with him again in 2003 when "The Simpsons" was about to broadcast its 300th episode. We started with this clip, featuring the Simpsons around the dinner table with their guest Krusty the Clown.

GROSS: I want to ask you about some of the characters that didn't exist in the very beginning stages of "The Simpsons," starting with Krusty the Clown, who's this really funny character. I mean, he's basically like an old vaudevillian type - really bitter and, you know, Jewish (laughter) like a lot of comics and, you know. But this is like an old-style Jewish comic - clown. What did you think of Krusty when he was first created?

GROENING: Well, Krusty was based on a TV show clown that -who I grew up with in Portland, Oregon named Rusty Nails. Rusty Nails was a Christian clown. He was a - he had his own show, and he showed old "Three Stooges" shorts. And he was great. And he wasn't like Krusty at all. He was very nice - very nice guy and very sweet clown. But he had the name Rusty Nails, which I found incredibly disturbing as a child because, you know, you're supposed to avoid rusty nails. So (laughter) the idea of a clown named Rusty Nails...

GROSS: You were a sensitive little kid.

GROENING: Well, you know, clowns are scary to begin with. And even though this was a nice clown, I was slightly perturbed by him.

GROSS: You know, we spoke just as "The Simpsons" was coming into existence, starting first as a Tracey Ullman series. And I think we spoke just as it was about to be broadcast on its own. And a lot has happened since then. (Laughter).

GROENING: Yes.

GROSS: "The Simpsons" has taken over the world since then. I'm wondering how your vision of the characters as they are now compare with the vision you had when you were creating them.

GROENING: (Laughter) Well, here's the problem with doing a sitcom which has lasted more than 300 episodes is you're trying not to repeat yourself. You're trying to surprise the audience. And you're trying to keep everybody who works in the show surprised. As a result, the show has gone off in some very peculiar directions. Sometimes, I was alarmed - OK, oh my God, we can't do this. We can't do this. And then it turns out to be OK. One of the great things we did last year was we parodied the Fox News Channel. And we did the crawl on the bottom of the screen. And Fox fought against it and said that they would sue. They would sue the show. And we just - we called their bluff because we didn't think Rupert Murdoch would pay for Fox to sue itself. So we got away with it. But now Fox has a new rule that we can't do those little fake news crawls on the bottom of the screen in a cartoon because it might confuse the viewers into thinking it's real news.

(LAUGHTER)

GROSS: What are some of the other things that you have been threatened legally over or, you know, that have been really controversial - advertisers pulling out? Because let's face, it "The Simpsons" does a lot of satire about homosexuality, the Church, you know, violence on television.

GROENING: Yeah, you know, at the beginning, virtually anything we did would get somebody upset. And now it seems like the people who are eager to be offended - and this country's full of people who are eager to be offended - they've given up on our show. We got into trouble a few years ago for - Homer was watching an anti-drinking commercial. And it said, warning, beer causes rectal cancer. And Homer responds by saying, mmm, beer. Fox didn't want us to do that because beer advertisers are part of the Fox empire. And it turns out that the writer was able to track down the actual fact where some studies show that, indeed, it does or did or has a tendency to, so we were able keep that in. That's the kind of thing we put up with.

GROSS: We'll hear more of our 2003 interview with Matt Groening after a break as we conclude our tribute to "The Simpsons" This is FRESH AIR.

(MUSIC)

GROSS: This is FRESH AIR. In anticipation of the 12-day Simpsons TV marathon, which begins tomorrow on FXX, we've been featuring interviews from our archive about the show. Let's get back to our 2003 interview with the creator of "The Simpsons," Matt Groening.

(SOUNDBITE OF ARCHIVED BROADCAST)

GROSS: Let's talk about Itchy and Scratchy. And this is the recurring cartoon that Bart and Lisa watch on TV. And it's the kind of, like, super violent version of all the cat and mouse kind of cartoons. How'd you come up with this?

GROENING: Well, it was from watching cat and mouse cartoons growing up. Pixie and Dixie, the Hanna-Barbera mice and "Tom and Jerry" in particular - very, very violent and very, very funny cartoons - MGM cartoons. And the fantasy was wanting these cartoons to extend their violence even more. So with Itchy and Scratchy, it's as extreme as it can get for a cat and mouse cartoon. We've done so many of them that they're harder and harder to write. And originally of the actors, Harry Shearer, who's a sophisticated guy, seemed to laugh the hardest at Itchy and Scratchy during the table reads. I think he's - I don't know if he's the voice of Itchy or Scratchy, but (high-pitched) he's the voice of one of them - he talks like that. Dan Castellaneta is the voice of the other one.

GROSS: So did you - were you in on the writing of the Itchy and Scratchy theme song?

GROENING: Yeah. Well, yeah, that was obvious. It's - by the way, it's not - everybody thinks it's they fight and fight and fight and fight and fight. It's not. It's they fight and bite and fight and fight and bite.

GROENING: The lyrics to that were written by Sam Simon, one of the original producers who developed show along with Jim Brooks and basically set the tone for the show.

GROSS: One of the characters is Ned Flanders. He's the Simpson's born-again neighbor. And, you know, so the kids in the Flanders household are being brought up very differently than the kids in the Simpson's household. Can you talk about the creation of Ned Flanders?

GROENING: Originally, Ned Flanders was just the wacky neighbor who was supposed to be just a complete annoyance to Homer for no good reason. And then we realized that he was an object of mirth with his strong religious feelings. We thought how do we create a religious character who is not the usual stereotype? And we made him a truly good guy. And his beliefs are sometimes a little annoying, but he's not a hypocrite. He's real. And we get lots of fan mail for him. And we get lots of photos of people who look exactly like Ned Flanders.

(LAUGHTER)

GROENING: Some people think Michael Medved is a Ned Flanders clone. So...

GROSS: That's funny.

GROENING: And I love the character. Harry Shearer does the voice and he does a fantastic job with finding variations on "okely dokely." And I think we treat the character with some dignity.

GROSS: Matt Groening is the creator of "The Simpsons." That interview was recorded in 2003.

CASTELLANETA: (As Homer Simpson) You've been rubbing my nose in it since I got here. Your family is better than my family. Your beer comes from farther away than my beer. You and your son like each other. Your wife's butt is higher than my wife's butt. You make me sick.

SHEARER: (As Ned Flanders) Simpson, I'm afraid I'm going to have to ask you to leave. I hope you understand.

CASTELLANETA: I wouldn't stay on a bet. (Drinking) One for the road.

GROSS: You know how the series often features actors and how celebrities often play themselves? Well, sometimes the writers aim lower, which is how I got a bit part in the episode "The DeBarted," which is a parody of Scorsese's film "The Departed." In this scene, Homer has just rented a car and he's driving with Lisa.

(SOUNDBITE OF TV SHOW, "THE SIMPSONS")

SMITH: (As Lisa Simpson) This car is amazing. The radio lets me contribute directly to NPR.

GROSS: (As herself) This is Terry Gross from NPR, saying thank you. Now let's get back to our 1987 interview with Senator Alan Cranston.

SMITH: (As Lisa Simpson) I never dreamed an American car designed in Germany, assembled in Mexico from parts made in Canada could be so amazing.

CASTELLANETA: (As Homer Simpson) Yeah, I can't believe all those years I used to drive that old piece of - what the?

GROSS: Recording that scene was really fun. I was alone in the FRESH AIR studio. My director was listening to me from LA. He gave me what I think is the most amusing professional advice I've ever gotten, which is - sound more like a cartoon version of yourself. The 12-day Simpsons marathon, featuring all 552 episodes in sequential order, begins tomorrow morning at 10 on the FXX cable network. We'll close with "The Simpsons" tribute to "A Streetcar Named Desire."